Label holder for automatic car identification system

ABSTRACT

An Automatic Car Identification (ACI) system for identifying individual railroad cars includes an information label on each car that can be scanned by a beam from a source of radiant energy at a scanner mounted adjacent to the track of motion of the car. That portion of the radiant energy which is reflected from coded modules of the label is received and processed at the scanner to produce classification signals indicative of the label being scanned. An improved support for the components of the label has a plurality of inclined surfaces which carry the modules in such a manner that the coded reflective surfaces in each module are directed toward the optical center of the system at the scanner.

United States Patent 1 Seamon [1111 3,745,355 51* July 10,1973

[ LABEL HOLDER FOR AUTOMATIC CAR IDENTIFICATION SYSTEM [76] Inventor: James H. Seamon, 7928 Kingwood Avenue, Afton, Mo. 63123 [22] Filed: Dec. 14, 1971 [21] Appl. No.: 207,879

[52] US. Cl..l 250/219 D, 250/223 R, 40/133 R Primary Examiner-walter Stolwein Attorney-George H. Spencer. Robert S. Auten et all.

[57] ABSTRACT An Automatic Car Identification (ACI) system for identifying individual railroad cars includes an informa tion label on each car that can be scanned by a beam from a source of radiant energy at a scanner mounted adjacent to the track of motion of the car. That portion of the radiant energy which is reflected from coded modules of the label is received and processed at the scanner to produce classification signals indicative of the label being scanned. An improved support for the components of the label has a plurality of inclined surfaces which carry the modules in such a manner that the coded reflective surfaces in each module are directed toward the optical center of the system at the scanner.

7 Claims, 9 Drawing Figures Patented July 10, 1973 v 3,745,355

3 Sheets-Sheet 1 I PRIOR ART PRIOR ART FIG] PRIOR ART FIG.3

Patented July 10, 1973 3 Sheets-Sheet 15 LABEL HOLDER FOR AUTOMATIC CAR IDENTIFICATION SYSTEM BACKGROUND OF THE INVENTION This invention relates to means for mounting the car label forming a part of the Automatic Car ldentification, (AC1), system now in use in this country to identify railroad cars.

1n the ACI system, visible light is utilized for transmitting the railroad car identification, as provided by a car information label, to wayside readout equipment. In general, the system includes the car label, a scanner to read the label, and decoding-transmitting equipment operatively associated with this scanner.

The scanner has a viewing face pointed toward a track over which railroad cars pass and, through the use of a rotating scanning drum, with a plurality of mirror surfaces, a high intensity beam of white light is caused to sweep a vertical area of the side of a railroad car passing the viewing face. The car label is mounted on the car within the range of this vertical area so that the beam of light sweeps over the label as the car passes the scanner. p l

The portion of the beam of light which strikes the retro-reflective strips that comprise the car label is reflected back to the scanning drum and through a partially silvered mirror into a lens system that focuses the light onto a slit which defines a single strip of the car label at the scanning distance. The light transmitted through the slit is directed onto a dichroic mirror which allows passage of orange light but reflects blue light. The orange light passes through an orange transmitting filter to actuate a photomultiplier element. The blue light passes through a blue transmitting filter to actuate a second photomultiplier element. Thus, four different signals may be indicated by a stripe in the car label: orange, blue, orange and blue, and neither orange or blue.

Each car label includes a vertical array of horizontally placed. colored strips of retro-reflective material arranged as coded modules to designate the car identification number. Each "module is comprised of two stripes, approximately three-eighths inches wide and 6 inches long and the stripes are either orange, blue, checkered white or black. By different combinations of the two stripes and by reversing the order it is possible to obtain identifying signals from the two photomulti plier elements for the 10 digits from to 9 inclusive plus a start and stop indication.

For a more complete discussion of the features of the AC1 system reference is made to the Stites et al. U.S. Pat. on Mark Sensing, No. 3,225,177 issued on Dec. 21, 1965.

As this AC1 system dependson the proper reflection of the scanning beam from the retro-reflective strips of the modules, it is important that this reflected beam be of sufficient intensity. it has been found that the angle of incidence with which the scanning beam strikes the modules of the label has an important bearing on the amount of light reflected from the retro reflective strips of the label. In turn the angle of incidence at which the light beam impinges on the various areas of the label is dictated by the optical center of the scanner and the location of the label on the car passing the center line of the scanner window.

Because of the number of different types of railroad cars now in use on the railroads of the U.S. it is obvious that the location of labels, as applied to the various cars, will vary to some extent. Equally obvious is the fact that, even though label location may vary, they must all be within some defined zone so that the scanning beam can sweep over all the modules in the label in order for the system to operate.

In considering a defined zone for label placement the fixed placement of the scanner at the side of the track over which the cars move, is, of course, a limiting factor. According to instructions promulgated by the Association of American Railroads (AAR) the center line of the scanner window 1 should be located inches above the top of the rail in the track and the face of the scanner is to be inches from the closest label and 141 inches from the furthest label to be scanned.

Another factor which must be considered in connection with a defined zone of scan is the position of the label on a car when it is loaded and when it is empty. Naturally an unloaded car rides higherthan the loaded car and therefore the label on the: empty car is further above the top of the rail than is the same label when the car is loaded.

In summary the scanning beam must be able to cover a scanning field which exists between the near depth (105 inches) and the far depth (141 inches) as well as a vertical range which is determined to some extent by the load condition of the car. With reference to this vertical range label application instructions of the AAR provide that the height of the lowest label module be no less than 16 inches above the top of the rail while the height of the highest label module be no more than 1 14 inches. Generally this scanning field can be visualized as an elongated rectangular area which is vertically disposed with respect to the track and lies to the side of the track.

Because of the relatively large scanning field which the scanning beam must cover in an operative system the beam must sweep over an angular range of from some 17 above the optical center of the scanner to some 33- below the center in order to scan the highest and lowest modules which might be encountered.

Also because of the relatively wide angular sweep of the scanning beam in the vertical plane it is apparent that the light will strike the labels which may be located within the field of scan, at different angles of incidence during a vertical sweep. Thus a label strip directly opposite the optical center of the scanner will receive the light normal to its surface. However on either top or bottom side of this label the light beam will strike other modules at an angle of incidence and these angles range from some 15 at the top of the field of scan to some 32 at the lower end of the field of scan.

While the retro-reflective strips of the label are designed to reflect light back in approximately the same direction as received, it has been found that the amount of light which is reflected is reduced as the angle of incidence increases. This results in less light being received back at the scanner, and a consequently reduced efficiency of the system, when the angle of incidence becomes relatively large, as for example, at the vertical extremities of the scanning field. In particular a problem has existed for some time with regard to reading those labels which are located on low lying cars to lie within the lowest limit of the scanning field and where the angle of incidence is relatively large.

These low labels are found, for example, on flat cars where the label must, because of the low profile of such cars, be mounted at essentially the lowest limit of the field of scan. Because the labels cannot project above the floor surface of the flat car they must depend from the car and the obvious solution of raising the labels to increase scanning efficiency is therefore definitely precluded.

Another limiting factor in locating a label on a low lying car is found in the Equipment Diagram, Plate B, promulgated by the Mechanical Division of the Association of American Railroads (AAR), for cars to be used in interchange service. This diagram specifies profile limits of dimensions for cars, with respect to the track, beyond which no part of the car, the equipment carried on the car, or lading can project if the car is to be received in unrestricted interchange between railroads. If these requirements are not met the car must receive special handling at considerable expense. Consequently, as a matter of business practice, the location of the label on a low lying car is very much dictated to be within a very restricted range which leaves little room for moving the label to improve scanning efficiency.

Extensive efforts have also been made to improve the scanner optics which are somewhat less efficient for low labels. While some progress has been made the problem of reading low labels still exists.

SUMMARY OF THE INVENTION Therefore, it is an object of this invention to provide a means for mounting a label on a low lying railroad car in such a manner that the scanning efficiency of the ACI system associated with the label is increased, while at the same time the rigid requirements with respect to the placement of equipment on such cars is fully met.

Generally the above described object of the invention is achieved by providing a label holder or support means in which a plurality of tilted or inclined surfaces are arranged to receive the individual strips for the modules of the label. The base portion of the label holder may be flat for conventional mounting on a side portion of the car or if required the base portion can be arranged in sections to lie in different planes so as to readily fit within the Plate B requirements. In either case the inclined surfaces projecting outward from the base portion do so at an angle of some 30 so that these surfaces, on which the retro-reflective strips are carried, are disposed essentially normal to the scanning beam of light. As thus disposed, within the profile limitations of Plate B, the retro-reflective strips reflect with an unexpected degree of efficiency and, as a result, the overall operation of the ACI system, when reading low lying labels, is enhanced.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a diagrammatic view showing the location of the scanner with respect to the scanning field for labels on railroad cars.

FIG. 2 is also a diagrammatic view showing a flat car with a label mounted on the side of the car.

FIG. 3 is a view ofa section of a car similar to the car shown in FIG. 2 and showing the label mounted on a side sill.

FIG. 4 is a view of a portion of another type of low lying railroad car showing a label on a bracket.

FIG. 5 is a diagrammatic view showing the angles of incidence with which light from a scanner impinges on retro-reflective strips of a car label within the scanning field.

FIG. 6 is a front elevation view of one embodiment of a label holder.

FIG. 7 is a side view of the label holder shown in FIG.

FIG. 8 is a sectional view taken along the line 8-8 in FIG. 6.

FIG. 9 is a side view of another embodiment of the invention.

PREFERRED EMBODIMENTS OF THE INVENTION FIG. 1 of the drawing shows the placement of the ACI system scanner, generally shown at 10, with respect to the rails 11 and 12 of the track over which railroad cars, one of which is shown in outline form by dashed lines and generally indicated by the reference number 13, can move past a scanning face 14 of scanner 10. In a known manner, as revealed, for example, in the Stites et al. US. Pat., No. 3,225,177, the scanner utilizes an optical system to scan information labels on the cars in order to identify individual cars. As this patent disclosed the system in which the label holder is used it is not believed necessary to give a detailed description of the entire system other than to describe those spatial relationships between the scanner and the information label on the car which are important to an understanding of the present invention.

Before proceeding with a more detailed description of the invention, it should be pointed out that placement of the scanner at the track wayside and its scanning mode is determined by the equipment itself and by the manufacturer of the equipment working in conjunction with railroad industry. Thus the effective optical center of the scanner, generally indicated at 15, is specified to be located inches above the tops of rails 11 and 12. The scanning beam emitted at the scanner face 14 is directed towards the track so as to move in a vertical plane which is fixed within the range of a 1 1 to 14 displacement from a vertical plane passing through the optical center and normal to the rails. The center of scan of the beam is indicated by line 16 which is angularly displaced downward from the horizontal plane by approximately 11, as shown.

Because the car label used in the ACI system can be located at various areas on different types of railroad cars it is important that, in some manner, each label be mounted in a position within the scanning range of the scanner. As previously explained, this scanning field, in which the label is placed is specified by instructions promulgated by the Association of American Railroads, is enclosed by the solid lines, and generally indicated at 17 as superimposed on the outline of car 10.

While the size of the scanning field 17 generally permits a rather large selection of positions for label mounting on most cars, this is not the situation in the case of low lying cars. Attention is directed to FIGS. 2 and 3 which show the manner of mounting conventional labels, generally indicated at 18, on a flat car, shown generally at 19.

In FIG. 2, a permissible area within the scanning field in which the label 18, shown with horizontal hatch lines, can be mounted is defined by other hatch lines and this extends for some distance longitudinally of the car 19. However, with respect to choice of vertical placement, this is extremely limited. It will be recalled that the labelling instructions of the AAR provide that the lowest module of the label be no less than 16 inches above the top of rail in the track.

In addition to this lower limit requirement of 16 inches, the label, however mounted on a particular type of low lying car, must not extend beyond the profile limits imposed by Plate B, a portion of which is shown by the dash-dot line 20, in FIG. 3 where the label 18 is shown mounted flat against the side sill 21 of the car 19. This profile limit is likewise illustrated in FIG. 4 where the profile limit 20 is shown in connection with another type of low lying railroad car used for trailer on flat car movements. The car, a portion of which is generally shown at 22, has a support bracket, generally indicated at 23, with a dependent plate 24 for the label 18 and a support member 25.

With respect to the upper limit of label placement it will be observed, in FIG. 2, that this is set essentially at the floor level, as it is in FIG. 4, or other types of low lying cars.

At this point it is desirable to generally describe the label of the ACIsystem and the two basic methods of applying the labels to the railroad cars. This label consists of 13 modules and, as previously mentioned, each module has a coded combination of two strips of retrorefiective material, for representing start, stop, 0 through 9, and a used as a validity check digit. The standard module is 1 inch high by 5 8/10 inches .wide. A retro-reflective material used in such labels is,

for example, a Silver Scotchlite Brand number 230 which is manufactured by Minnesota Mining and Manufacture Co. of St. Paul, Minn.

These modules are applied directly to a prepared surfaceon the car or to a separate support surface in a ladder pattern to form the complete label. The separate support surface can be a suitable rigid metal backing or mounting plate and the present invention is concerned with an improved separate support means for the label.

Referring again to FIGS. 3 and 4, the conventional label 18 has heretofore been applied to low lying cars, whether directly to the car, as in FIG. 3, or to a separate support surface, such as the dependent plate 24, to be essentially vertically positioned with respect to the track. Consequently, because such mounted labels lie well below the optical center of the scanner 10, the angles of incidence of light striking the modules of the labels 18 is relatively great as compared to those labels located more directly opposite or above the optical center 15. This situation is diagrammatically illustrated in FIG. 5 where the angles indicated are the angles of incident light to the normal.

Because of the large angles of incidence with which the light beam from the scanner l0 sweeps low lying modules on low lying cars a very significant portion of this radiant energy is dispersed and is not reflected from the modules back to the scanner 10. This loss of ef'ficiency is avoided in the label arrangement, according to the invention, which will be described now in more detail.

In FIGS. 5-7 a first embodiment of the label holder is generally indicated at 26 and it will be observed that the holder includes a flat base 27, of rectangular shape, and a plurality of louvers 28 which project from the central portion of this base. The holder is formed from a metal plate in which the louvers are stamped in a shape to be described later. A number of openings 29,

at the corners and center edge of the base, are provided for mounting the label holder on a low lying car in a suitable manner within the scanning field, as for example, according to the methods shown in FIGS. 3 and 4.

As best seen in FIGS. 6 and 8, the louvers 28 are ar ranged in a ladder configuration and there are flat border portions 30, 31, 32, and 33 remaining along the top, side and bottom edges respectively, of the base 27, as viewed in FIG. 6. Each louver 28 is stamped along a slit line 34 and all of these slit lines provided for the plurality of louvers are spaced in parallel relation, as also shown in FIG. 6. Each louver has sloping side walls 35 that are integral with a flat wall 36 projecting outward from base 27 at an angle a with respect to the plane of base 27 as indicated in FIG. 8. In a first embodiment of the invention the louvers are disposed so that the flat wall is inclined at an angle of approximately 30 relative to the base.

It will be recalled that the individual modules of the complete label are formed with coded strips of retroreflective material and the inclined flat walls 36 of the louvers 28 receive the modules. For the sake of clarity in disclosing the features of the label holder 26 only one module, generally indicated at 37, is shown mounted on the flat wall 36 of the second from the top louver 28. The module itself is conventional and has the retro-reflective strips 38 and 39 arranged in a coded combination and secured by a suitable adhesive, not shown.

In order that the light beam from the scanner 10 can pass over all modules in a label mounted on the label holder 26 and carried on a car it is obviously necessary that the inclined surfaces 36 of the louvers 28 do not overlap in the line of sight from the optical center 15 of the scanner. Thus there must be a base portion, generally shown at 40, lying between the slit line 34 of one louver and the fold line 41 of the next lower louver.

When the label holder 26 illustrated in FIGS. 68 is mounted on a low-lying car with its base 27 vertically oriented relative to the track over which the car moves pass a scanner 10, the modules 37 on the holder are inclined toward the optical center 15 of the scanner. At an inclination of approximately 30 the light beam from the scanner strikes the individual modules 37 at the lower end of the scanning field 17 almost normally and the amount of light reflected back to the scanner is greatly increased.

It should be stressed that, in mounting the label holder 26 on a low lying car, the holder should be within the profile limits imposed by Plate B requirements. In certain situations it may be necessary to two vide a label holder which, because of these requirements, cannot be one with entirely a flat base in one plane. A second embodiment of the invention is shown in FIG. 9 where a composite label holder is, generally, indicated at 42.

In this holder the base is formed of a flat top portion 43 and a flat lower base portion 44 which are secured together with the lower base portion inclined relative to the top base portion.

The second embodiment has louvers 28, as in the first embodiment, to carry the modules of a label and it is not thought necessary to fully repeat a description of the structure. However, it is important to point out that the louvers 28 formed in the top base portion 43, which is designed to be mounted vertically with respect to the railroad track, are inclined at approximately 30 relative to the base portion, while those louvers 28 on the lower base portion 44 are inclined at a greater angle a so that, with respect to the vertical plane of the top base portion 43, they too are inclined at approximately 30. As thus arranged modules carried on both top and lower base portion of the holder, as mounted on a railroad car, face the scanner at the same angle as the car moves over the track in front of the scanner.

The above described arrangement permits the composite label holder 42 to be mounted on a low lying car to fit within a profile line so as to meet Plate B requirements.

While the above description of label holders has been concerned with those in which louvers are pressed from a plate it should be understood that the invention is not restricted to a louver construction. Thus the holder can be formed in any desired manner with inclined surfaces in a ladder-like arrangement, as for example, by a casting or molding process.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

I claim:

1. In an optical to electronic signal translating system for identifying objects passing a scanner,

1. aninformation label on the object with a plurality of modules having code combinations of strips of material with a surface which reflects radiant en- 2. an optical system, having an optical center adjacent a face of the scanner which is directed toward the object, for scanning the information label with radiant energy in a scanning raster transversing the label in a direction substantially orthogonal to the direction of relative motion between the object and the scanner,

3. a system at the scanner for receiving the radiant energy reflected from the strips of the label and for producing classification signals in response thereto, the improvement which comprises, a

mounting means for the information label with a base portion that is secured to the object to extend along the object in the area which lies below that portion of the object that passes directly opposite the optical center of the scanner as the object moves past the scanner, a plurality of shaped projections, each with a surface inclined with respect to said base portion extending forward from said base portion in a direction away from the object and disposed in a ladder type vertical position, said shaped projections being disposed in vertically spaced relationship with no overlap between adjacent inclined surfaces in the line of sight from the optical center, and with the modules of the label mounted on the inclined surfaces whereby the reflecting surfaces of the strips of each module are directed upwardly toward the optical center of the scanner face.

2. The improvement as defined in claim 1, wherein said inclined surfaces of said shaped projections are disposed at an angle of approximately 30 with respect to the plane of said base portion.

3. The improvement as defined in claim 1, wherein said base portion of said mounting means is secured to the object in an inclined position with the top module of the label being closer to the optical center than is the lowest module of the label.

4. The improvement as defined in claim 3, wherein said inclined surfaces of said shaped projections are disposed at an angle greater than 30 with respect to the plane of said base portion.

5. The improvement as defined in claim 1, wherein a top portion of said base portion is secured to the object in a vertical position normal to a horizontal plane extending through the optical center to the object, and a lower portion of said base portion is inclined inwardly with respect to the plane of said top portion of said base portion.

6. The improvement as defined in claim 5, wherein the inclined surfaces of said shaped projections on said top portion are disposed at an angle of approximately 30 with respect to the plane of said top portion and the inclined surfaces of said shaped projections on said lower portion are disposed at an angle greater than 30 with respect to the plane of said lower portion.

7. The improvement as defined in claim 1, wherein the plurality of shaped projections are in the shape of louvers. 

1. In an optical to electronic signal translating system for identifying objects passing a scanner,
 1. an information label on the object with a plurality of modules having code combinations of strips of material with a surface which reflects radiant energy,
 2. an optical system, having an optical center adjacent a face of the scanner which is directed toward the object, for scanning the information label with radiant energy in a scanning raster transversing the label in a direction substantially orthogonal to the direction of relative motion between the object and the scanner,
 3. a system at the scanner for receiving the radiant energy reflected from the strips of the label and for producing classification signals in response thereto, the improvement which comprises, a mounting means for the information label with a base portion that is secured to the object to extend along the object in the area which lies below that portion of the object that passes directly opposite the optical center of the scanner as the object moves past the scanner, a plurality of shaped projections, each with a surface inclined with respect to said base portion extending forward from said base portion in a direction away from the object and disposed in a ladder type vertical position, said shaped projections being disposed in vertically spaced relationship with no overlap between adjacent inclined surfaces in the line of sight from the optical center, and with the modules of the label mounted on the inclined surfaces whereby the reflecting surfaces of the strips of each module are directed upwardly toward the optical center of the scanner face.
 2. an optical system, having an optical center adjacent a face of the scanner which is directed toward the object, for scanning the information label with radiant energy in a scanning raster transversing the label in a direction substantially orthogonal to the direction of relative motion between the object and the scanner,
 2. The improvement as defined in claim 1, wherein said inclined surfaces of said shaped projections are disposed at an angle of approximately 30* with respect to the plane of said base portion.
 3. The improvement as defined in claim 1, wherein said base portion of said mounting means is secured to the object in an inclined position with the top module of the label being closer to the optical center than is the lowest module of the label.
 3. a system at the scanner for receiving the radiant energy reflected from the strips of the label and for producing classification signals in response thereto, the improvement which comprises, a mounting means for the information label with a base portion that is secured to the object to extend along the object in the area which lies below that portion of the object that passes directly opposite the optical center of the scanner as the object moves past the scanner, a plurality of shaped projections, each with a surface inclined with respect to said base portion extending forward from said base portion in a direction away from the object and disposed in a ladder type vertical position, said shaped projections being disposed in vertically spaced relationship with no overlap between adjacent inclined surfaces in the line of sight from the optical center, and with the modules of the label mounted on the inclined surfaces whereby the reflecting surfaces of the strips of each module are directed upwardly toward the optical center of the scanner face.
 4. The improvement as defined in claim 3, wherein said inclined surfaces of said shaped projections are disposed at an angle greater than 30* with respect to the plane of said base portion.
 5. The improvement as defined in claim 1, wherein a top portion of said base portion is secured to the object in a vertical position normal to a horizontal plane extending through the optical center to the object, and a lower portion of said base portion is inclined inwardly with respect to the plane of said top portion of said base portion.
 6. The improvement as defined in claim 5, wherein the inclined surfaces of said shaped projections on said top portion are disposed at an angle of approximately 30* with respect to the plane of said top portion and the inclined surfaces of said shaped projections on said lower portion are disposed at an angle greater than 30* with respect to the plane of said lower portion.
 7. The improvement as defined in claim 1, wherein the plurality of shaped projections are in the shape of louvers. 